Paraffin scraper



a. J. FESTERVAN ETAL 2,225,413

PARAFFIN SCRAPER Dec. 11, 1940.

Filed Oct. 19, 1938 ATTORNEY.

BY W? I 1 Patented Dec. 1340 F ,5 th ee; S A-res {PA N I errce Henderson, I

7 Claims. (Cl. res-1's) The present invention is directed to a device for scraping parafiln from the interior of tubes arranged in oil wells. More specifically, it is directed toa fluid operated rotating drill for the remo'valof'parailln from said tubes One of the important problems in the tion of oil from subsurface iormations, isthe accumulation of paraflln'on the interior of tubes which lead theoil from the producing iorm'ation 1 to ,the surface. Most oil contains paraiiln which, at the temperature, obtaining at the depth at which the oilis produced, is in the liquid state As the oil is caused to flow toward the surface,

. K temperature decreases untila point is reached H 5 at which the paraflin crystallizes out and accumulates on the walls of the tubes. In time this accunnilation .becomessufliciently great to stop the flow oroil" to the surface and to present a removal problem which is at once time-consuming and expensive. 1

The object of the present invention is to provide a device whichmay V through which the oil is produced and which carries cutting edges which are rotatedby the flow of fluid in the tubing while at the same time the device is moved longitudinally of the tubing. The deviceis so constructed that it operates to cut the parafllnwax oi? the walls of the tubing whether it is, allowed to move downwardly.

through the tubing under. static well conditions or is .caused to move upwardly through the tubing under flowingwell conditions. g

An additional object of the present invention is to pr ovide a device of the character described which willvbe simple in construction, inexpensive and" durable. N

Further objects and advantages of the present invention will appear from the following detailed descriptibn' oi the accompanying drawing in 40 which v 1 Fig. 1 is a side view ofthe complete device;

Fig.2 is a side view of the body portion of the V v device with the-cutters removed;.

Fig. 3 is a side view of a removable cap adapted to be secured to the upper end of the complete device;

Fig. 4 is amend view of one of thee utters; and Fig. 5 is a side view, in section, q! a removable cap adapted to be secured to the lower end 'of the complete device e Referring tothe drawing in detail, numerel -l designates an elongatedbody portion or any desired, cross-sectional configuration, but- Prefer be placed in the tubing interior, with a weighting material such asmercury or water if desired. At each of its ends 1" produc- A body I is provided with a nip le 3, each of said 5 nipples being provided with t eads 4 and with a smooth bearing portion 5 intermediate said threads and the main body portion. Flxed on each of the bearing portions 5 is a ring gear 8 which is provided with spiral grooves I which are 6 so pitched; preferably at about as to impart a lifting and rotating action to the body portion when fluid passing longitudinally along said body portion passes through said groove. )Io this end the ring gears are made with an outside diameter 15 which is only a'small fraction of an inch, say; about less than the inside diameter, of the r tubing in which the device is to operate.

One end 3 of the body-portioncarries a screw threaded cap 8 the outer end of which is plO- 20 ,vided with a socket having an inner cylindrical cavity 8 the outer endof which is provided with shoulder in from which the wall flares outwardly as at H to the outer end of the cap-8. This cap 'is placed on the upper end of the device and 25.

serves as a receiving socket for .a fishing tool.

by abutting. against a stop'arranged for that understood that this'sto .struction that it willenot impede the flow of oil I tion, a stop of anysuitable construction is located 40 purpose in the tubing- It will be. observed thatthese removable caps serve the? additional iunc- 35 tion oi rendering the cutting gears replaceable whereby the life of the assembly as a whole is not limited by thelife oil the cutting edges;

In utilizing the device of the present invenin the tubing at a point where the temperature issuch that paraflin re ains liquid. It will be i: must be of such a conthrough it. The flow oioil through the tubing 45 'is stopped and the device of the present invention is introduced into the top oi the tubing, through which it moves downwardly by the force of gravity. In its downward movement iluid' g through the groove 1 causes the device to so rotate and imparts to it the action of a rotary drill. Whenthe device reaches the 'stop the pper, end of the tubingisopened. to permit the 1 ably circularfto minimizethedesistance torota- Lf-flbwoi oil. 'I'hemovemen't of oil upwardly im- 55 tion, which maybesoiid or hollowas shown in partsa'liiting and rotating actioh'to thescraper.

It is important to note thatin this movement the scraper is set into rapid rotation before it reaches theparamncoatingonthewallswherebyinits upward movement the device also has the action 0! a rotary drill.

It will understood that the embodiment shown in the drawing is for illustrative purposes only and can be modified both as to size. shape and arrangement of parts without departing from the scope of the present invention. For example, while two ,cuttlng gears are illustrated, only one will suffice. Again it is to be noted that the cutting gears maybe rigidly fixed to the elongated body or may be journaled for relative rotation with respect thereto. In the latter case, the device may be allowed to drop freely through the tubing, but should be moved upwardly by a wire line. Likewise, the cutters may be made in any desired configuration and a separate disk provided on the elongated body portion to accomplish rotation thereofl upon movement thereof relative to the oil in the tubing.

We claim:

i 1. A device for removing paraflin from the inside of a vertical oil-carrying tubing comprising an elongated buoyant body adapted to be moved freely within said tubing by the action 01- flowing mild in the tubing, a laterally projecting cutting disk arranged on said body adjacent each end thereof, inclined passages arranged longitudinally in each of said disks for the flow offiuid therethrough, a blunt-nosed cap for securing one of said disks to said body and a cap provided with the end of said blunt-nosed cap is constructed or shock absorbing material. a s

3. A device in accordance with claim 1 in which the end 0! said blunt-nosed cap is constructed of rubber.

4. A device for removingparailin from the inside of a vertical oil-carrying tubing comprising an elongated buoyant tubular body adapted to be moved freely within said tubing by the action or fiowingfiuid in said tubing, a laterally projecting cutting disk arranged on said body adjacent each end thereof, inclined passages arranged longitudinally-in each at said discs for the fiow of fiuid therethrough, and a cap arranged on each end of said body for. sealing the interior oi said body in a fluid tight manner.

5. A device in accordance with claim 4 in which 20 one of said caps is provided with a cavity for a fishing tool.

6. A device in accordance with claim 4 in which one of said caps is provided with a blunt nose constructed oi a shock absorbing. material. 25

v 7. A device in accordance with claim 4 in which one of said caps is provided with a cavity for a fishing tool and theother cap is provided with a blunt nose constructed of a shock absorbing material. r r

NATHAN E. HENDERSON. BENJAMIN J. FESTERVAN. 

